Music Question

I recently went from the Motorola M to the Motorola X. I was reluctant to give up my external SD card slot ....On my old phone anytime i downloaded music from any free Music Download app it automatically saved in GOOGLE PLAY so i could access all my music there to listen to. now anytime i download music from an app i can ONLY access it in that app. how on earth do i get all my music back to GOOGLE play? how can i get any music i download to automatically save back to there?? i'm so frustrated!!

Welcome to Android Central
I'm assuming it's because before, when you had the SD card, it would save there and allow Google Play to access it as well. Now it downloads into a folder for that specific app.
If I'm right, all you need to do is plug the phone into a PC and move the music files from inside the app's folder and move it onto the phone again, not into any specific folder